A triangle has corners at (8,5), ( 2, -7),and( 1, -2 )#. If the triangle is reflected across the x-axis, what will its new centroid be?

1 Answer
May 18, 2018

(113,43)

Explanation:

begin by calculating the coordinates of the centroid

given the coordinates of the vertices of a triangle say

(x1,y1),(x2,y2) and (x3,y3)

then the centroid is the average of the x and y
coordinates of the vertices

centroid =[13(x1+x2+x3),13(y1+y2+y3)]

[13(8+2+1),13(572)]=(113,43)

under a reflection in the x-axis

a point (x,y)(x,y)

(113,43)(113,43)new centroid